Spring core for innerspring mattresses and the like



W. LEHMANN Dec. 5, 1967 SPRING CORE FOR INNERSFRING MATTRESSES AND THE LIKE 2 Sheets-Sheet l Filed March 29, 1966 Dec. 5, 1967 W. LEHMANN 3,355,746

SPRING CORE FOR INNERSPRING MATTRESSES AND THE LIKE Filed March 29, 1966 2 Sheets-Sheet y WML? United States Patent ilice 3,355,746 Patented Dec. 5, 1967 ABSTRACT F THE DISCLSURE Spring core for innerspring mattresses and the like in which quadrangular cores are arranged in rows with two legs of each winding of the spring cores parallel to the plane of the core and aligned with corresponding legs of adjacent spring coils and with line wires wound around the aligned legs of the spring coils.

The present invention concerns a spring core for innerspring mattresses, seats, upholstered furniture, and the like, with adjacent interconnected springs.

It is an object of the present invention to provide a spring core which will permit a good resiliency of spring core mattresses, seats, upholstered furniture, and the like.

It is another object of this invention to provide la spring core which, when under load, will adapt its shape to the person resting thereon while at the same time the spring core will be prevented from being compressed beyond an undue large area under a load acting on a point or narrow surface only.

It is also an object of this invention to provide a spring core which may be made particularly at while also the edges of the spring core will be elastic.

Still another object of this invention consists in the provision of a spring core which will permit making the outer surfaces of the spring core plane so that it will be easy to cover the spring core with textiles or the like material.

Finally, it is an object of the present invention to provide a spring core as set forth above which will be rel-atively inexpensive to manufacture and which will have a low weight.

These and other objects and advantages of the invention will appear more clearly from the following specification in connection with the accompanying drawings, in which:

FIG. l diagrammatically illustrates in top view a cutout of a spring core according to the invention.

FIG. 2 is an isometric view of a cutout portion according to FIG. 1.

FIG. 3 represents a portion of a further embodiment of a spring core according to the invention.

A spring core according to the present invention `for innerspring mattresses,` seats, upholstered furniture, and the like with adjacent springs, which are interconnected, is characterized primarily in that the springs, when viewed in their longitudinal direction, have square or rectangularshaped coils or helices of at least three windings while the outermost coils or helices are at least partially plane parallel to the plane of the mattress or the like, and in the longitudinal direction of the mattress and/or in the direction of the width thereof, the spring legs arranged approximately in straight line one behind the other and pertaining to the outer spring coils are interconnected at least partially be helically bent ne wires. By means of the said helically bent line wires, the individual springs are elastically interconnected so that when the spring core is under a load acting upon a small surface only, only a small area surrounding said surface under load will be compressed. In view of this connection of the springs, a

particularly progressive effect will be obtained. The outer surfaces of the spring core may be designed particularly simple in view of the springs having a relatively small 'approximately square or similar cross section.

According to a further feature of the present invention, the ends of the fine wires are bent at a right angle and are wound about the outer legs of the marginal springs which are -approximately parallel to the ends of the tine wires. In this way, the said line Wire ends will bring about an additional reinforcement within the edge areas of the spring core so that a frame band steel will not be necessary.

According to a further feature of the present invention, the outermost spring windings which are plane parallel to the mattress are formed by three or more legs forming angles with each other so that tine wires may be wound about each two legs arranged at an angle with regard to each other, whereas the free ending leg is inclined toward the core center so that the cover of Ia mattress, of a seat or of a piece of furniture to be placed upon the spring core cannot be damaged by the said free end.

It has proved advantageous so to select the pitch of the spring coils that it corresponds approximately to the length of the edge of the spring.

According to a further feature of the present invention, each two legs of the spring coil which merge with each other are inclined to the plane of the spring core, whereas the two adjacent legs are parallel to the plane of the spring core. In this way, it is possible to provide the spring core with line wires also in the planes which are located between the planes of the large outer surfaces of the spring core. By means of said line wires, a progressive spring effect will be assured which is such that the spring core, even when under considerable load, will not `be compressed completely.

Advantageously, the springs which are located adjacent to each other in the longitudinal and/or in the direction of width of the spring core are offset with regard to each other by so that when being compressed, the springs A particularly advantageous further development of the present invention is obtained by interconnecting by more fine wires those edges of the legs In addition thereto, have a particularly low weight while nevertheless being characterized by a very elastic and shape-maintaining edge of the spring core.

It is also possible to form those edges of the spring core which are parallel to the spring core plane by means of a flat frame of steel or round wire or the like which is connected to the springs in any convenient manner, e.g. by welding.

By employing rectangular springs, preferably springs' with square-shaped or trapezoidal contour, it is possible to form a narrow mesh structure at the surface of the spring core so that the cover for covering the spring core may be selected especially thin which in turn again brings about a saving in material and weight, which is particularly advantageous in connection with mattresses.

Referring now to the drawings in detail, FIGS. l and 2 thereof illustrate a spring core according to the present invention which comprises springs 1 extending in the longitudinal direction (indicated by the arrow 3) of the spring core and also in transverse direction (indicated by the arrow 4) of the spring core. These springs 1, when viewing the spring core from the top, have a rectangular shape. The said springs are in transverse direction (arrow ..3 4) arranged in rows 5 one alongside the other, whereas the said springs in the longitudinal direction (arrow 3) f the spring core are arranged serially in rows 6, 7.

The individual springs are connected by means of tine wires 8 to 10 extending in transverse direction (arrow 4) of the spring core and are furthermore interconnected by fine wires 11 to 13 in the longitudinal direction (arrow 3) of the spring core.

As will be evident from FIG. 2, the outermost spring winding 14 of springs 1 are located in planes parallel to the plane of the spring core, while the said windings are each formed by three legs 15, 16, 17 arranged at a right angle with regard to each other. The next two legs 18, 19 which follow the outermost winding 14 are inclined with regard to the plane of the spring core while the adjacent legs 20, 21 of spring 1 are again located in a plane parallel to the plane of the spring core. The inclination of legs 18, 19 is so selected that the space between legs 20, 21; 15, 16, which are located plane parallel to the spring core in the longitudinal direction of spring 1, equals approximately the length of legs 15, 16, 19, 18, 20, 21 respectively. With the embodiment illustrated in the drawings, legs 1S, 16 and 20, 21 are located in four planes parallel to each other.

The two end legs 17 of each spring 1 are inclined toward the center of the spring core so that they will not damage the covers to be placed on the spring core.

As will also be evident from F1G. 1, the springs 1, when viewed from the top, have a substantially trapezoidal contour while two adjacent legs 1S, 16; 20, 21 are at a right angle with regard to each other, and the two oppositely located legs 18, 19 form with each other an angle of slightly less than 90.

Springs 1 of the spring rows 6, 7 extending in the longitudinal direction (arrow 3) of the spring are in said rows arranged in positions corresponding to each other. Springs 1 of those rows 6, 7 which are adjacent to each other in the transverse direction (arrow 4) of the spring core and which extend in the longitudinal direction (arrow 3) of the spring core are oifset with regard to each other by 90 so that for instance the spring legs 17 of the said adjacent rows 6, 7 are offset with regard to each other by 90.

Springs 1 are so arranged that in the longitudinal direction and in the transverse direction of the spring core, each leg 16, 20, and 15, 16; 21, 20 is along a straight line and plane parallel to the plane of the spring core located one behind the other. It is around these legs of spring 1 that the helical ne wires S to 13 are wound. In the marginal area of the spring core, the outermost windings 14 are interconnected through two fine wires 8, 9; 11, 12 extending in the same direction whereby an additional reinforcement of the spring core marginal area 2 will be obtained.

Instead of reinforcing the spring margin 2 by means of two or more ne wires 8, 9; 11, 12, it is also possible to reinforce the marginal area 2 of the spring core by one or more at steel frames 22 in conformity with FIG. 3, said frame 22 being connected to marginal springs located in the marginal area of the spring core, e.g. by welding.

Inasmuch as springs 1 of those spring rows 6, 7 which in longitudinal direction of the spring core are arranged alongside each other are offset with regard to each other, there are always two ne wires 13 arranged directly adjacent to each other in the longitudinal direction of the spring core, whereas the ne wires extending in the transverse direction of the spring core are always spaced by slightly more than the width of the spring.

The ends 23 of the ne wires 8 to 13 are bent at a right angle and wound about those legs of the corresponding springs 1 which form the marginal area 2 of the spring core.

It is, of course, to be understood that the present invention is, by no means, limited to the particular arrangements shown in the drawings, but also comprises any modifications within the scope of the appended claims.

What I claim is:

1. A spring core, especially for innerspring mattresses, seats and upholstered furniture, which includes: a plurality of identical coil springs arranged behind and alongside each other so as to form rows of springs extending in the longitudinal direction and in the transverse direction of said spring core, the windings of each of said coil springs when viewing the coil spring in its longitudinal direction being such that a projection of each of said coil springs in the longitudinal direction thereof defines a quadrangle, each winding of each said coil spring cornprising two interconnected legs extending substantially parallel to the plane of the spring core and at right angles to each other while the other two legs incline toward the next winding of the respective spring, the said two interconnected legs of each of the two outermost windings of each coil spring respectively being located in substantially the outer planes of said spring core, each coil spring along the margin of the core having a said interconnected leg in the adjacent margin of the core, adjacent rows of coil springs in at least one of said directions of said spring core having adjacent ones of said interconnected legs in approximately axial alignment with each other, the coil springs of each longitudinal row of springs being in one and the same rotated position while the coil springs in each row are displaced from those of the adjacent rows, and ne wire means coiled around and interconnecting said approximately axially aligned legs of adjacent coil springs pertaining to adjacent rows of coil springs, the rotated relation of said coil springs providing that the said fine wire means are located in adjacent pairs extending through the spring core in the longitudinal direction while said ne wire means extending transversely of the core are spaced the same distance apart as adjacent spring coils.

2. A spring core according to claim 1, in which the fine wire means which extend longitudinally of the spring core have their end portions bent off at 90 and coiled around the legs of the coil springs at the margin of the spring core.

3. A spring core according to claim 1, in which the pitch of the windings of the spring coils equals approximately the length of one of the said interconnected legs of a spring winding.

4. A spring core according to claim 1, in which the free ends of the coil springs are inclined toward the interior of the spring core.

5. A spring core according to claim 1, in which the said interconnected legs of those coil springs which are located at the marginal areas of said spring core are interconnected by at least two ne wire means.

6. A spring core according to claim 1, which includes flat frame means connected to the outermost spring coils at the marginal areas of said spring core.

References Cited UNITED STATES PATENTS 1,337,320 4/1920 Karr 5-269 2,473,706 6/1949 Gleason 5-269 2,547,904 4/19571 Elder 5-269 X FOREIGN PATENTS 170,314 2/1952 Austria.

835,338 3/1952 Germany.

503,897 4/1939 Great Britain.

BOBBY R. GAY, Primary Examiner. R. D. KRAUS, Assistant Examiner. 

1. A SPRING CORE, ESPECIALLY FOR INNERSPRING MATTRESSES, SEATS AND UPHOLSTERED FURNITURE, WHCIH INCLUDES: A PLURAILTY OF INDENTICAL COIL SPRINGS ARRANGED BEHIND AND ALONGSIDE EACH OTHER SO AS TO FORM ROWS OF SPRINGS EXTENDING IN THE LONGITUDINAL DIRECTION AND IN THE TRANSVERSE DIRECTION OF SAID SPRING CORE, THE WINDINGS OF EACH OF SAID COIL SPRINGS WHEN VIEWING THE COIL SPRING IN ITS LONGITUDINAL DIRECTION BEING SUCH THAT A PROJECTION OF EACH OF SAID COIL SPRING IN THE LONGITUDINAL DIRCTION THEREOF DEFINES A QUADRANGLE, EACH WINDING OF EACH SID COIL SPRING COMPRISING TWO INTERCONNECTED LEGS EXTENDING SUBSTANTIALLY PARALLEL TO THE PLANE OF THE SPRING CORE AND AT RIGHT ANGLES TO EACH OTHER WHILE THE OTHER TWO LEGS AT RIGHT ANGLES NEXT WINDIG OF THE RESPECTIVE SPRING, THE SAID TWO INTERCONNECTED LEGS OF EACH OF THE TWO OUTERMOST WINDINGS OF EACH COIL SPRING RESPECTIVELY BEING LOCATED IN SUBSTANTIALLY THE OUTER PLANES OF SAID SPRING CORE, EACH COIL SPRING ALONG THE MARGIN OF THE CORE HAVING AN INTERCONNECTED LEG IN THE ADJACENT MARGIN OF THE CORE, ADJACENT ROWS OF COIL SPRINGS IN AT LEAST ONE OF SAID DIRECTIONS OF SAID SPRING CORE HAVING ADJACENT ONES OF SAID INTERCOINNECTED LEGS IN APPROXIMATELY AXIAL ALIGNMENT WITH EACH OTHER, THE COIL SPRINGS OF EACH LONGITUDINAL ROW OF SPRINGS BEING IN ONE AND THE SAME ROTATED POSITION WHILE THE COIL SPRINGS IN EACH ROW ARE DISPLACED 90* FROM THOSE OF THE ADJACENT ROWS, AND FINE WIRE MEANS COILED AROUND AND INTERCONNECTING SAID APPROXIMATELY AXIALLY ALIGNED LEGS TO ADJACENT COIL SPRINGS PERTAINING TO ADJACENT ROWS OF COIL SPRINGS, THE ROTATED RELATION OF SAID COIL SPRINGS PROVIDIENG THAT THEL SAID FINE WIRE MEANS ARE LOCATED IN ADJACENT PAIRS EXTENDING THROUGH THE SPRING CORE IN THE LONGITUDINAL DIRECTION WHILE SAID FINE WIRE MEANS EXTENDING TRANSVERSELY OF THE CORE ARE SPACED THE SAME DISTANCE APART AS ADJACENT SPRING COILS. 